AOJ 0518 The Oldest Site
http://rose.u-aizu.ac.jp/onlinejudge/ProblemSet/description.jsp?id=0518
解けそうだったので・・・。
set
main(){ int n; while(cin>>n,n){ set<PI> app; rep(i,n){ int x,y; cin>>x>>y; app.insert(mp(x,y)); } int ans=0; FOR(iter,app){ FOR(jter,app){ int tx=iter->F-jter->F,ty=iter->S-jter->S; if(tx*tx+ty*ty<=ans)continue; if(app.count(mp(iter->F-ty,iter->S+tx)) && app.count(mp(jter->F-ty,jter->S+tx)))ans=tx*tx+ty*ty; } } cout<<ans<<endl; } }